Carbon: An Important Element — Science STD 9 — Question

Write a note on : Potential

What is meant by space observation? Why is it important?

What will be the nature of the graph between the current and potential difference? (Do not draw a graph.)

The minimum distance between the start and finish points of the motion of an object is called the ……….. of the object.

Write note on :

Pteridophyta

As compared to the monsoons and winter a very small quantity of urine is produced in the summer season. Why is it so?

Define :

Alkali

Take a fresh and fleshy leaf of Rhoeo, lily or any other plant. Pull and press it, tearing it obliquely in such a way that its transparent epidermis will be visible at the cut margins. Take the transparent epidermis with the forceps and keep it in dilute safranin solution for 1 minute. Spread it on a slide, cover it with a cover-slip and observe it under a compound microscope.

Even though the magnitudes of action force and reaction force are equal and their directions are opposite, their effects do not get cancelled.

Electronic definition of Valency